Welcome to APSIM

The Agricultural Production Systems sIMulator (APSIM) is internationally recognised as a highly advanced simulator of agricultural systems. It contains a suite of modules which enable the simulation of systems that cover a range of plant, animal, soil, climate and management interactions. APSIM is undergoing continual development, with new capability added to regular releases of official versions. Its development and maintenance is underpinned by rigorous science and software engineering standards. The APSIM Initiative has been established to promote the development and use of the science modules and infrastructure software of APSIM.

NEWS

The APSIM Initiative Reference Panel has provided two examples for connecting APSIM to optimisation techniques. These serve to demonstrate contrasting approaches in connecting APSIM to optimisation software.

International users of APSIM can now enjoy easy access to APSIM metrological files (.met files) from NASA POWER via a new R package developed by USQ’s Associate Professor of Field Crops Pathology Dr Adam Sparks called nasapower now available on CRAN. One of the functions in this new package takes the NASA POWER agroclimatology data and reformats it into an APSIM .met file for use in APSIM simulations. Information and documentation for the new package can be found at https://ropensci.github.io/nasapower/.

As a user of APSIM, you may access and modify all source code. As per the conditions agreed to on download, all modifications to APSIM must be submitted to the AI and be subject to the Reference Panel evaluation process before inclusion into the official APSIM release. Updated instructions for submitting Improvements to APSIM for review by the APSIM Initiative Reference Panel can be found here.

It can be useful to notify the APSIM Initiative that you are planning on making an improvement to APSIM. This can often lead to others suggesting ideas or collaborators to work with. To do this you need to create an issue in GitHub with a description of what you intend doing. This is for APSIM 7.x and APSIM Next Generation. Any queries, please email apsim@csiro.au.

The plan outlines work that is currently being undertaken by APSIM Initiative Members and partners. It covers work that is being carried out this year as well as planned or aspirational work in the near future.

If you’re interested in more information, co-developing or partnering in any of this work, please email apsim@csiro.au.

FEATURES

In a recently published article Teixeira et al. (http://dx.doi.org/10.1016/j.envsoft.2015.05.012) used APSIM to assess the impact of different methods of representing the initial conditions of the soil.In climate impact studies, weather data are commonly taken over a 20-30 year period to assess inter-annual variability of crop production.Often, for simplification, individual crops (monocultures) are sown on the same date every year and soil water and nitrogen are reinitialised to default values prior to planting (re-initialised monoculture). However, in reality crops are often grown in a rotation and the soil conditions they encounter at planting are the result of the water and nitrogen balances of the preceding crops and fallow periods.APSIM is able to construct realistic rotations and represent carryover effects of crop sequences. Teixeira et al. simulated a continuous wheat (grain) ® wheat (forage) ® kale (forage) ® maize (grain) rotation over a 30 years to compare with re-initialised mono-culture simulations. The production, water use and soil nitrogen of simulated crops were all sensitive to the method of simulation (re-initialised mono-culture vs. continuous rotation) and the sensitivities were greatest when inputs (water and nitrogen) were lowest. This paper shows that greater emphasis should be placed on obtaining suitable initial conditions for simulating crop production, particularly for low intensity crop production systems. It is difficult to achieve this in single crop simulations, which illustrates the benefit of representing the carryover of soil conditions across multiple crops grown in a sequence as performed with APSIM in this study.

In March 2016, agricultural systems modellers will meet in Berlin, Germany, for an international symposium, coordinated by scientists from Germany, Finland, Australia and the USA. The agricultural systems modelling network spans the whole globe and more than 300 participants are expected to show up for the event, organized by the Leibniz Centre of Agricultural Landscape Research in Müncheberg, Germany. Crop models have developed into indispensable tools in the ongoing discussion on global food security, but only their consistent application through global co-operation assures their usefulness and credibility at the interfaces of agronomy with economics and in informing policy-making. Additional details can be found on the symposium flyer or website www.icropm2016.org.

Over 24 years, the Agricultural Production Systems sIMulator (APSIM) has grown from a farming systems framework used by a small number of people, into a large collection of models used by many thousands of modellers internationally. The software consists of many hundreds of thousands of lines of code in multiple programming languages. This infrastructure has successfully integrated a diverse range of models but isn’t capable of easily meeting new demands from modellers. For these reasons, the APSIM Initiative has begun developing a next generation of APSIM (dubbed APSIM next generation) that is a completely new application with no legacy code and designed to run across different platforms. Currently APSIM next generation has limited capability and isn't quite ready for mainstream use. However, if your modelling problems fits within the specified capability, or you simply wish to evaluate this release, then it can be downloaded from the APSIM registration page (look for 'next generation' in the version drop down box). More information can also be found here.

Palm oil is an important vegetable oil, produced from oil palm grown by many companies and more than a million smallholders worldwide. For growers to make decisions that are good for productivity and the environment, they need to know which practices are best for crop yield, soil fertility, aquatic ecosystems, and to minimise greenhouse gas emissions. Recent collaboration between ACIAR, James Cook University, CSIRO and the PNG Oil Palm Research Association has developed an Oil Palm model for APSIM. The model simulates palm growth and development in response to climate, soil and management. Training workshops have been held in PNG, Indonesia and Malaysia. A paper describing the new model is available at the following link.

In December 2014, the journal 'Environmental Modelling and Software' published the first part of a new Thematic Issue: "Agricultural systems modelling and software: current status and future prospects". Lead by Dean Holzworth (with 7 co-authors), the Thematic Issue explores the current status of the leading process based agricultural systems models. Models featured in the Issue include APSIM, AquaCrop, CropSyst, STICS / RECORD, APSIM PMF and APSIM OilPalm. There are also a range of other papers covering various aspects of modelling complex agricultural systems. For more information go to the following link.
Part 2 of the Thematic Issue (including a position paper) will be published mid 2015.